Abstract: An angle measuring device includes an antenna device having antenna elements equally spaced along a first axis and a second axis, respectively, a selecting unit that selects phase differences with which a variance thereof becomes a predetermined value or less, from a plurality of phase differences of signals received from a transmission device by the antenna elements, an azimuth angle computing unit that computes an azimuth angle of the transmission device from a ratio of a first phase difference between signals received by two antenna elements spaced by a predetermined distance along the first axis and a second phase difference between signals received by two antenna elements space by the predetermined distance along the second axis, and an elevation angle computing unit that computes an elevation angle of the transmission device, based on the computed azimuth angle and the first or second phase difference.

Abstract: In order to provide a receiver capable of accurately determining a phase difference of I/Q signals, a receiver includes a section detector configured to detect a section between a rising and a falling of a phase based on the rising and the falling of the phase represented by I/Q signals generated based on an advertisement packet transmitted from a transmitter, and a section setting unit configured to identify, within the section between the rising and the falling of the phase, a period in which a first variation amount of the phase is equal to or less than a first predetermined amount, and use the identified period as a section for detecting the phase of the I/Q signals. The section detector detects the rising when a first phase is smaller than a last phase among a plurality of phases acquired by sampling the phases.

Abstract: A communication method includes: transmitting, by a transmitter, advertising packets having different data lengths per transmitting channel; and identifying, by a receiver, a transmitting channel of an advertising packet based on data length information contained in header information in the advertising packet, and the receiver receives remaining data in the advertising packet when the identified transmitting channel and a receiving channel match, and not receive the remaining data in the advertising packet when the identified transmitting channel and the receiving channel do not match.